A newly revealed plot to kill Churchill with exploding chocolate prompts an investigation into history's weirder ways to assassinate.

This is a young Castro playing ping pong shirtless. No known assassination attempts involved ping pong, oddly. (AP)

"Dear Fish, I wonder if you could do a drawing for me of an explosive slab of chocolate," begins a letter from Lord Victor Rothschild, a British
intelligence officer in World War II. "We have received information that the enemy are using pound slabs of chocolate which are made of steel with a very
thin covering of real chocolate. Inside there is high explosive and some form of delay mechanism."

The letter, which was sent on May 4, 1943 to Laurence Fish, an illustrator, referenced a very real assassination plot by the Nazis. Their target: no less
than the round mound of resolve, Prime Minister Winston Churchill. The chocolates were to be placed
"amongst other luxury items in the War Cabinet's dining room where Winston Churchill often hung out." But the plan was discovered by British spies and
(ahem) foiled.

This exploding-chocolate story has just come to light this week in the British papers, and it got me thinking. Could this be the most bizarre assassination
technology? Surely not. So I went looking for some more.

Hitler himself was almost done in by an exploding briefcase planted not by a spy, but by a member of his military during a coup attempt. His press secretary said of the attack, "The German people must consider the failure of the
attempt on Hitler's life as a sign that Hitler will complete his tasks
under the protection of a divine power."

But perhaps the best place to look was the annals of the Central Intelligence Agency. As detailed in the Church Committee report of the 1970s, the agency was
constantly plotting to kill the leaders of countries that it perceived too anti-American or pro-communist. In grinding detail, the reports reconstruct the
various CIA efforts, none of which appear to have succeeded.

On the very plausible sounding end of the spectrum, there was the plot to kill the first Congolese Prime Minister, Patrice Lumumba. A CIA agent simply picked a
biological agent from a list of substances available the Army Chemical Corps at Fort Detrick, Maryland, and stuck it in a bottle along with gloves and a
syringe. The idea was to get the substance onto some kind of food or perhaps into his toothpaste, which Lumumba would have eaten, and thereby contracting the illness. Among the candidate
diseases were: tularemia ("rabbit fever"), brucellosis (undulant fever), tuberculosis, anthrax, smallpox, and Venezuelan equine encephalitis ("sleeping
sickness").

And then there are the attempts to kill Fidel Castro, which were detailed in a book, The Fish Is Red, as well as a British documentary called, " 638 Ways to Kill Fidel Castro." Still, I prefer the Church Report's droll
retellings of the plots.

First, there were the poison cigars:

A notation in the records of the Operations Division, CIA's Office of Medical Services, indicates that on August 16, 1960, an official was given a box
of Castro's favorite cigars with instructions to treat them with lethal poison. The cigars were contaminated with a botulinum toxin so potent t,hat a
person would die after putting one in his mouth. The official reported that the cigars were ready on October 7, 1960 ; TSD notes indicate that they
were delivered to an unidentified person on February 13,196l. The record does not disclose whether an attempt was made to pass the cigars to Castro.

Then, we read about the poison pills, an alternative to a "gangland-style killing," in that the method was "nice and clean, without getting into any
kind of out and out ambushing." The pills contained botulinum toxin and were manufactured to dissolve in water, so they could be dropped into Castro's
drink. They were given to a shady underworld figure with Las Vegas contacts, who apparently somehow got them to someone in the Castro government, but
nothing came of the plot.

The CIA seemed to perceive that Castro was vulnerable near or in the ocean. In 1963, they seriously examined "whether an exotic seashell, rigged to
explode, could be deposited in an area where Castro commonly went skin diving." Basically, an EXPLODING CONCH SHELL.

And they explored giving him a diving suit that been "dusted ... with a
fungus that would produce a chronic skin disease (Madura foot), and contaminated the breathing apparatus with a tubercule bacillus." Apparently, the
CIA's tech folks bought the suit and did the contamination, but it never left the lab.

And who could forget the poison pen, "a ball-point pen rigged
with a hypodermic needle" filled with Blackleaf-40 poison? Apparently, it was kind of a kludgey assassination device, though. The CIA contact in Cuba who was given the pen, "did not
'think much of the device,' and complained that CIA could surely 'come up with something more sophisticated than that.'"

Of course, the Soviets had their share of assassination technologies, too. One is so famous it even has a name, "The Bulgarian Umbrella," and a Wikipedia page. Quoth the people's encylopedia:

The Bulgarian umbrella is the name of an umbrella with a hidden pneumatic mechanism which shot out a small poisonous pellet containing ricin. The Bulgarian Umbrella has a hollow stalk which the pellet neatly sits into.

The Israeli intelligence services are suspected of killing Yehiya Ayyash with his own cellphone, which the group had rigged as a bomb. The History Channel dramatized how easy it is to turn a cellphone into a bomb. As one retired Shin Bet officer put it, "Half the battery can be dynamite." Yikes.

In recent years, the world witnessed the truly horrifying assassination of former KGB agent turned journalist, Alexander Litvinenko, in London. A rare radioactive isotope polonium-210 was placed in his tea during a lunch at a sushi restaurant. He fell ill and died a slow death from the radiation poisoning. Several Russian officers have been suspected of the killing.

Of course, most assassinations don't come through fanciful cloak-and-dagger activity. Without the complexities of the Cold War to deal with, drones do most of the covert killing. At least for the United States.

(Thanks to @gbrumfiel, @haleyhennes, @jodyavirgnan, and @monbud for their help with this story.)